[Locutus28]

Okay all you New Beetle Techies! Let's put our heads together and see if we can figure this out. First of all, I have a Code Scanner and attached it to my 1999 New Beetle, 2.0L Gas Engine. It gave me a OBDII Code of 17990. I have gone through two MAF Sensors. Here is the thing. My bug can't make up it's mind. The Engine Lite will go off by itself, some times for two or three weeks and then come back on. Later on (another week or so) it will go off again. Isn't it nice to have a car that fixes itself? What do you think is going on.

Some previous posts have talked about cleaning the intake manifold. This bug as 125,000 miles on it. Would it make sense for me to take the Intake Manifold Off and take it to a machine shop to have it cleaned, or am I wasting my time. What is the best way to go about this? Can't wait till I hear what you have to say!

 

[Smileybug]

I would try a throttle body alignment. Not sure why you went through 2 MAFs for this code though (if that's why you went through 2 of them). Check this link for more info: 17990/P1582/005506 - Ross-Tech Wiki

 

[Locutus28]

Ross Tech Wiki

Thank you for your help, Smiley Bug. I went to the Ross site, but it seems they are talking about some kind of Diagnostic Software program. I just have the OBDII Scanner. If you think a Throttle Body Alignment is warranted, should I take it to a VW Dealer and have them do it?

 

[bme]

You could also take the intake boot off and push the plate back and clean out the throttle body (don't drop anything in there) and then button back up. I would also check for intake leaks because the code is saying the throttle body can no longer compensate for what is going on. U can buy a v-checker or a vag405 for less then a trip to the dealer and align the TB your self in adaptation mode.


Bme

 

[IndyTom]

The code that is showing has nothing to do with the MAF sensor or the intake manifold. It is a Throttlebody code which can be caused by a dirty Throttlebody, dirty fuel filter, bad fuel pump, the N80 EVAP Purge valve, bad fuel injectors, any number of vacuum leaks, leaky SAI Pump, exhaust leak, etc...

Start with cleaning out your Throttlebody with some Throttlebody cleaner, then double check all your vacuum lines and make sure they are not cracked or leaking. If you still are running the stock clothbraided covered lines replace them with some quality rubber or better yet silicone lines. Change your fuel filter if you haven't in a while. Put a Bottle of Seafoam in the fuel tank before filling up next time to clean out the injectors. Check the connections to your SAI (Secondary Air Injection) pump. Do you hear a screeching noise when you start the car in the morning? Could be the Sai pump leaking. There are a slew of possible solutions. Start with the easy ones before you start replacing parts that don't need replacing.